upgrade: use standard Tab accessor

Yes, the formula object does refer to a version that has not yet been
installed, but we were not looking into Formula#prefix, but #linked_keg,
which is version agnostic (since the original patch was committed, we
Tab#for_formula learned to look into #opt_prefix as well). The rest of
the logic is already embedded in the Tab accessors.
audit: warn about nonexistent options passed to deps
mtr: use new optional deps support

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
postgresql: use new recommended deps support

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
gnome-doc-utils: depend on libxml2 'with-python'

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
subversion: universal is now passed to deps automatically
vtk: use current tab API
pdf2svg: depends on poppler with-glib
diffpdf: depends on popper with-qt4
duplicity: make universal optional

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
jbigkit: make universal optional

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
libgcrypt: make universal optional

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
libgpg-error: make universal optional

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
librsync: make universal optional

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
Percona Server 5.5.29

Closes #17318.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
Percona Toolkit 2.1.8

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
openrtsp 2013.01.25

Closes #17321.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
locks: ensure lock directory exists

Fixes #17326.
FormulaInstaller: wrap --build-from-source in an Option object

c.f. #17327.
mjpegtools: use new optional deps